From patchwork Thu Sep 16 08:40:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanna Czenczek X-Patchwork-Id: 12498313 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FEEEC433EF for ; Thu, 16 Sep 2021 08:53:48 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F3AD260F4C for ; Thu, 16 Sep 2021 08:53:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org F3AD260F4C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:39582 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mQn9P-000756-0p for qemu-devel@archiver.kernel.org; Thu, 16 Sep 2021 04:53:47 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48470) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mQmyh-0006w5-1r for qemu-devel@nongnu.org; Thu, 16 Sep 2021 04:42:43 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:47124) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mQmyf-0005aY-0P for qemu-devel@nongnu.org; Thu, 16 Sep 2021 04:42:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631781760; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=a7L6wJecFIS2hzEromfrddFGo+PgXoIROWmqA13TApg=; b=gszSbPU/d5NZ41wuLJxe0mL6xHCJLdypNBkXMsLc0r/QMFmng3mUkXkl2HBTD8HU/jiEbJ fWgnbUnUEmDkqi06Oni9Nt2HtVxoJntCtCqzPF2NsLtrVDZHfTso/k2y+NMdV+mRI8aZ0o PMGDl3mp3yThJVTkyrkeWOJmS9gwGS4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-258-mkbcOAUsO7m6oEqyI_-Wow-1; Thu, 16 Sep 2021 04:42:39 -0400 X-MC-Unique: mkbcOAUsO7m6oEqyI_-Wow-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4EE161005E46 for ; Thu, 16 Sep 2021 08:42:38 +0000 (UTC) Received: from localhost (unknown [10.39.192.150]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 24B295D9CA; Thu, 16 Sep 2021 08:42:30 +0000 (UTC) From: Hanna Reitz To: qemu-devel@nongnu.org, virtio-fs@redhat.com Subject: [PATCH v4 12/12] virtiofsd: Add lazy lo_do_find() Date: Thu, 16 Sep 2021 10:40:45 +0200 Message-Id: <20210916084045.31684-13-hreitz@redhat.com> In-Reply-To: <20210916084045.31684-1-hreitz@redhat.com> References: <20210916084045.31684-1-hreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=hreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=hreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.39, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Hanna Reitz , Stefan Hajnoczi , "Dr . David Alan Gilbert" , Vivek Goyal Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" lo_find() right now takes two lookup keys for two maps, namely the file handle for inodes_by_handle and the statx information for inodes_by_ids. However, we only need the statx information if looking up the inode by the file handle failed. There are two callers of lo_find(): The first one, lo_do_lookup(), has both keys anyway, so passing them does not incur any additional cost. The second one, lookup_name(), though, needs to explicitly invoke name_to_handle_at() (through get_file_handle()) and statx() (through do_statx()). We need to try to get a file handle as the primary key, so we cannot get rid of get_file_handle(), but we only need the statx information if looking up an inode by handle failed; so we can defer that until the lookup has indeed failed. To this end, replace lo_find()'s st/mnt_id parameters by a get_ids() closure that is invoked to fill the lo_key struct if necessary. Also, lo_find() is renamed to lo_do_find(), so we can add a new lo_find() wrapper whose closure just initializes the lo_key from the st/mnt_id parameters, just like the old lo_find() did. lookup_name() directly calls lo_do_find() now and passes its own closure, which performs the do_statx() call. Signed-off-by: Hanna Reitz --- tools/virtiofsd/passthrough_ll.c | 93 +++++++++++++++++++++++++------- 1 file changed, 75 insertions(+), 18 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index e86fad8b2f..368bad17c7 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1348,22 +1348,23 @@ out_err: fuse_reply_err(req, saverr); } -static struct lo_inode *lo_find(struct lo_data *lo, - const struct lo_fhandle *fhandle, - struct stat *st, uint64_t mnt_id) +/* + * get_ids() will be called to get the key for lo->inodes_by_ids if + * the lookup by file handle has failed. + */ +static struct lo_inode *lo_do_find(struct lo_data *lo, + const struct lo_fhandle *fhandle, + int (*get_ids)(struct lo_key *, const void *), + const void *get_ids_opaque) { struct lo_inode *p = NULL; - struct lo_key ids_key = { - .ino = st->st_ino, - .dev = st->st_dev, - .mnt_id = mnt_id, - }; + struct lo_key ids_key; pthread_mutex_lock(&lo->mutex); if (fhandle) { p = g_hash_table_lookup(lo->inodes_by_handle, fhandle); } - if (!p) { + if (!p && get_ids(&ids_key, get_ids_opaque) == 0) { p = g_hash_table_lookup(lo->inodes_by_ids, &ids_key); /* * When we had to fall back to looking up an inode by its @@ -1392,6 +1393,36 @@ static struct lo_inode *lo_find(struct lo_data *lo, return p; } +struct lo_find_get_ids_key_opaque { + const struct stat *st; + uint64_t mnt_id; +}; + +static int lo_find_get_ids_key(struct lo_key *ids_key, const void *opaque) +{ + const struct lo_find_get_ids_key_opaque *stat_info = opaque; + + *ids_key = (struct lo_key){ + .ino = stat_info->st->st_ino, + .dev = stat_info->st->st_dev, + .mnt_id = stat_info->mnt_id, + }; + + return 0; +} + +static struct lo_inode *lo_find(struct lo_data *lo, + const struct lo_fhandle *fhandle, + struct stat *st, uint64_t mnt_id) +{ + const struct lo_find_get_ids_key_opaque stat_info = { + .st = st, + .mnt_id = mnt_id, + }; + + return lo_do_find(lo, fhandle, lo_find_get_ids_key, &stat_info); +} + /* value_destroy_func for posix_locks GHashTable */ static void posix_locks_value_destroy(gpointer data) { @@ -1930,14 +1961,41 @@ out: fuse_reply_err(req, saverr); } +struct lookup_name_get_ids_key_opaque { + struct lo_data *lo; + int parent_fd; + const char *name; +}; + +static int lookup_name_get_ids_key(struct lo_key *ids_key, const void *opaque) +{ + const struct lookup_name_get_ids_key_opaque *stat_params = opaque; + uint64_t mnt_id; + struct stat attr; + int res; + + res = do_statx(stat_params->lo, stat_params->parent_fd, stat_params->name, + &attr, AT_SYMLINK_NOFOLLOW, &mnt_id); + if (res < 0) { + return -errno; + } + + *ids_key = (struct lo_key){ + .ino = attr.st_ino, + .dev = attr.st_dev, + .mnt_id = mnt_id, + }; + + return 0; +} + /* Increments nlookup and caller must release refcount using lo_inode_put() */ static struct lo_inode *lookup_name(fuse_req_t req, fuse_ino_t parent, const char *name) { g_auto(TempFd) dir_path_fd = TEMP_FD_INIT; int res; - uint64_t mnt_id; - struct stat attr; + struct lookup_name_get_ids_key_opaque stat_params; struct lo_fhandle *fh; struct lo_data *lo = lo_data(req); struct lo_inode *dir = lo_inode(req, parent); @@ -1955,13 +2013,12 @@ static struct lo_inode *lookup_name(fuse_req_t req, fuse_ino_t parent, fh = get_file_handle(lo, dir_path_fd.fd, name, NULL); /* Ignore errors, this is just an optional key for the lookup */ - res = do_statx(lo, dir_path_fd.fd, name, &attr, AT_SYMLINK_NOFOLLOW, - &mnt_id); - if (res == -1) { - goto out; - } - - inode = lo_find(lo, fh, &attr, mnt_id); + stat_params = (struct lookup_name_get_ids_key_opaque){ + .lo = lo, + .parent_fd = dir_path_fd.fd, + .name = name, + }; + inode = lo_do_find(lo, fh, lookup_name_get_ids_key, &stat_params); release_file_handle(lo, fh, false); out: